Conclusion

This paper has examined the limitations and performance of both the logical and physical backup and restore strategies. Logical backup has the advantage of a portable archival format and the ability to restore single files. Physical backup and restore has the advantages of simplicity, high throughput, and the ability to support a number of data replication strategies. Both have much to contribute to a complete file system backup strategy, but that the ability of physical backup/restore to effectively use the high bandwidths achievable when streaming data to and from disk argue that it should be the workhorse technology used to duplicate our constantly growing data sets and protect them from loss.